JP2018032745A - Dresser, method of manufacturing dresser, and method of manufacturing semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polishing pad dresser that is excellent in productivity, and to provide a method of manufacturing the same.SOLUTION: A dresser 1 comprises: a base metal 10; and a chip part 20 provided on the base metal 10, and that includes an Si substrate having a projection on its upper part and whose plane orientation is a (111) plane, and a diamond thin-film layer formed on the projection of the Si substrate by using a plasma CVD method. Since the diamond thin-film layer is deposited on the Si substrate, an excellent high-temperature environment and a high productivity can be achieved compared with a case where the diamond thin-film layer is deposited on a metal-based substrate.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate to a dresser, a method for manufacturing a dresser, and a method for manufacturing a semiconductor device

About.

As a technique for planarizing an insulating film, a metal film, a polycrystalline silicon film, etc. embedded in a trench in a semiconductor device manufacturing process, chemical mechanical polishing (Chemical Mechanical Polishing)
al Polishing: CMP) is known. In CMP, the surface of the polishing pad is deformed with repeated polishing and the polishing ability is lowered. Therefore, in order to suppress this drop, the polishing pad is dressed using a dresser at regular intervals.

JP-A-10-71559 Special table 2014-522739 gazette

The problem to be solved by the present embodiment provides a dresser excellent in high productivity, a method for manufacturing a dresser, and a method for manufacturing a semiconductor device.

The dresser of the embodiment is provided with a base metal and a plurality of S on the base metal and having a protrusion on the top.
a chip portion including an i substrate and a diamond thin film layer provided on the protrusion of the Si substrate.

The figure explaining the dresser which concerns on 1st Embodiment. The figure explaining the detail of the chip | tip part of FIG. The figure explaining the manufacturing method of the chip | tip part of 1st and 2nd embodiment. The figure explaining the manufacturing method of the chip | tip part of 1st and 2nd embodiment. The top view of a mask. The figure explaining the manufacturing method of the dresser concerning a 1st embodiment. The figure which shows the specific example using the dresser 1. FIG. The figure explaining the dresser which concerns on 2nd Embodiment. The figure explaining the manufacturing method of the dresser which concerns on 2nd Embodiment.

  Hereinafter, embodiments for carrying out the invention will be described.

(First embodiment)
The dresser according to the first embodiment will be described with reference to FIGS. In the following description of the drawings, the same portions are denoted by the same reference numerals. However, the relationship between the thickness and the planar dimensions, the ratio, and the like are schematic, unlike the actual ones.

A configuration of the dresser 1 according to the first embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a schematic plan view showing the working surface of the dresser 1 of the present embodiment. The working surface is a surface facing a dressing object such as a polishing pad.

As shown in FIG. 1, the working surface of the dresser 1 has a plurality of chip portions 20 on a base metal 10. The base 10 includes, for example, stainless steel (SUS) or iron, but the material is not particularly limited. The chip part 20 is formed from, for example, a Si wafer (Si substrate). The size of the chip portion 20 is, for example, 1 mm to 50 mm, but the size of the chip portion 20 is not particularly limited in the present embodiment. In addition, the number of the chip portions 20 of the dresser 1 of the present embodiment is not particularly limited, but a plurality of the chip portions 20 facilitates uniform dressing.

Next, details of the chip unit 20 will be described. FIG. 2A is a schematic plan view of the chip portion 20.
FIG. 2B is a schematic cross-sectional view showing the AA ′ cross section of FIG.

As shown in FIGS. 2A and 2B, the chip unit 20 includes a substrate 21 and a plurality of protrusions 22 on the substrate 21. The protrusion 22 has a conical shape with a radius of about 0.15 mm, for example. In the chip part 20, the protrusions 22 are arranged in a honeycomb shape, for example, in order to form as many protrusions 22 as possible in one chip part 20. The protrusion 22 includes, for example, Si and is integrated with the substrate 21. As shown in FIG. 2B, a diamond thin film layer 23 is formed on the protrusion 22. The diamond thin film layer 23 is formed over the entire surface of the chip portion 20 including the protrusion 22 and the substrate 21 exposed from the protrusion 22. The diamond thin film layer 23 has a substantially uniform thickness. The arrangement of the protrusions 22 in the chip part 20 is not limited as shown in FIG.

Next, the manufacturing method of the chip part and the dresser according to the present embodiment will be described with reference to FIGS.

3 and 4 are schematic cross-sectional views showing a partial region of the Si wafer. In the following manufacturing method, there is no deviation due to the position in the Si wafer, and the wafer is formed in a substantially uniform structure over the entire surface of the wafer.

As shown in FIG. 3A, an Si wafer is first prepared. CV is applied to the base film 30 on the Si wafer.
It is formed using D (Chemical Vapor Deposition) method. The base film 30 is a TEOS film of about 500 nm, for example. In this embodiment, the Si wafer is generally used in the semiconductor manufacturing process, and is suitable because it has a certain hardness at a low price. In particular, a Si wafer (Si (111)) having a (111) plane orientation has a higher Vickers hardness (Gpa) (for example, 10.6 Gpa or more) because the crystal plane orientation is uniform, and is more suitable. Furthermore, it is suitable because it has a thermal expansion coefficient comparable to that of diamond (for example, 2.56 × 10 −6 / K or less) as compared with other high hardness materials. Si (111) means S in the crystal.
A structure having an atomic arrangement in which the distances between i are equal.

Next, a resist film 40 is formed on the base film 30 as shown in FIG. The resist film 40 is, for example, an i-line resist film. Thereafter, the resist film is exposed by, for example, i-line through a mask as shown in FIG. However, the wavelength and the like are not particularly limited.

Next, as shown in FIG. 3C, after the exposed resist film 40 is developed, the underlying film 30 is etched substantially vertically by dry etching using the resist film 40 as a mask. At this time, for example, CF ₄ gas or the like is used.

Next, as shown in FIG. 3D, the Si wafer is etched. For example, SF ₆ = 7
Etching is performed using a mixed gas of 0 secm, C4F8 = 200 sccm, and O ₂ = 500 sccm. When the etching is further advanced under the same conditions, the upper end of the Si wafer approaches a corner cone shape as shown in FIG. At the same time, the sizes of the resist film 40 and the base film 30 are also reduced. Finally, a plurality of conical protrusions 22 are formed on the Si wafer (FIG. 4 (
b)). The reduced resist film 40 and base film 30 fall between the protrusions 22.

Next, the resist film 40 and the underlying film 3 reduced by asher or NH4OH cleaning or the like.
Remove 0. Through the above steps, a protrusion having a desired shape such as a conical shape is formed.
An i-wafer is obtained.

Next, in order to separate the Si wafer on which the plurality of conical protrusions 22 described above are formed,
Dicing to a desired size yields a chip portion 20 that becomes a base plate (FIG. 6A).
For example, the chip unit 20 can acquire 160 chips or more in the case of a 300 mm wafer and 70 chips or more in the case of a 200 mm wafer, but the number of chips is not particularly limited.

Next, a diamond thin film layer 23 is formed on the tip portion 20. Diamond thin film layer 23
For example, using a plasma CVD method, the tip portion 20 is placed on a grounded anode provided in a decompression vessel and heated to 800 degrees. Thereafter, a mixed gas of methane and hydrogen is introduced under reduced pressure, a direct current of about 1000 V is applied to the cathode, and abnormal glow discharge is performed. The above forming method is an example. As described above, the tip portion 20 having the protrusion 22 on which the diamond thin film layer 23 is formed is obtained.

Next, as shown in FIG. 6B, a resin is applied to the back surface of the surface of the chip portion 20 where the protrusions 22 are formed, and is attached to a base metal 10 including, for example, stainless steel (SUS). As the resin, for example, a mixture of an epoxy resin and an amine adhesive or a mixture of an epoxy resin and a polyamidoamine adhesive is used. The base metal 10 has, for example, a ring-shaped structure, but is not particularly limited.

  As described above, the dresser 1 of the present embodiment is completed.

  Next, a specific example using the dresser 1 according to the present embodiment will be described.

FIG. 7 is a schematic diagram showing a configuration of a polishing apparatus 100 as a specific example using the dresser 1. As shown in FIG. 7, the polishing apparatus 100 includes a dressing mechanism 2, a polishing head 3, a nozzle 4, a polishing pad 5, and a rotary table 6. In addition, there may be a configuration that is not illustrated in part.

The rotary table 6 is supported from below on a rotary shaft (not shown), and rotates at a predetermined speed when the rotary shaft is driven to rotate by an external driving device.

A semiconductor wafer is located below the polishing head 3. The wafer is placed so that the surface to be polished faces the polishing pad 5 and is held by the polishing head 3. The polishing head 3 includes a mechanism that can press the wafer against the rotary table 6.

A nozzle 4 for discharging slurry is disposed above the rotary table 6. The slurry is, for example, cerium dioxide as abrasive grains.

During the polishing process, slurry is supplied from the nozzle 4 onto the polishing pad 5 and the polishing head 3 is lowered to bring the wafer into contact with the polishing pad 5. Then, the rotary table 6 and the polishing head 3 are rotated in the same direction. In this way, a semiconductor device is manufactured by polishing a predetermined material to be polished provided on the wafer.

The dressing mechanism 2 is provided with a dresser 1 on the polishing pad 5 side. The dresser 1 is arranged such that a plurality of protrusions 22 of the tip portion 20 are located on the surface (working surface) facing the polishing pad 5. The dressing mechanism 2 rotates the dresser 1 during or before and after polishing the wafer, and sharpens the polishing pad 5 while swinging the dresser 1. By providing the dressing mechanism 2, the surface of the passing region of the wafer can be conspicuous uniformly.

As described above, according to the dresser 1 according to the present embodiment, since the diamond thin film layer is formed on the Si substrate, the dresser resistant to a high temperature environment is formed as compared with the case where the diamond thin film layer is formed on the metal substrate. It becomes possible to do. For example, when a diamond thin film layer is formed, 80
It is possible to avoid the problem that the metal is eluted when exposed to a high temperature environment of 0 ° C., and the carbon in the metal grows to form soot. In addition, since the thermal expansion coefficients of the Si substrate and diamond are approximately the same, it is possible to avoid the possibility of cracks occurring in the diamond thin film layer due to a large difference in thermal expansion coefficient from diamond in a high temperature environment.

Furthermore, since the Si substrate is processed into a conical shape to form protrusions, the dressing of the polishing pad can be performed more efficiently. Also, compared to a quadrangular pyramid or other protrusion shapes, the polishing pad can be dressed between the protrusions. It becomes difficult to collect trash.

According to the method for manufacturing the dresser 1 according to the present embodiment, after forming protrusions on the Si wafer, the wafer is diced into a plurality of chips by a dicing process, and the obtained chip portion is attached to the base metal. Therefore, the number of dressers that can be manufactured from a single wafer increases, and the cost can be reduced.

(Second Embodiment)
Hereinafter, the dresser according to the second embodiment will be described with reference to FIG. The dresser according to the second embodiment is different from the first embodiment in that a chip holder is used between the base metal and the chip portion.

FIG. 8 shows the configuration of the dresser 1 according to the second embodiment. Since the structure of the chip part 20 is the same as that of the first embodiment, the description thereof is omitted. As shown in FIG. 8, the dresser 1 of the present embodiment has a base 10 and a plurality of chip holding bases 50 provided on the base 10, and chip parts 20 are respectively provided on the chip holding bases 50. Have.

The chip holder 50 includes, for example, stainless steel (SUS), but the material is not particularly limited. The base metal 10 may be made of the same material and may be integrated as a part of the base metal 10. Further, the number of chip holding bases 50 is not particularly limited, and at least one chip holding base 50 is sufficient. In the present embodiment, the chip holder 50 may be included in a part of the base 10.

  Next, the manufacturing method of the dresser 1 of this embodiment is demonstrated using FIG.

First, the chip part 20 is produced. In addition, since the formation method of the chip | tip part 20 is the same as that of 1st Embodiment, the description is abbreviate | omitted (refer FIG.3, FIG4 and FIG.6 (a) figure).

Next, the tip portion 20 on which the diamond thin film layer 23 obtained by the above method is formed is formed as a protrusion 22.
Resin is applied to the back surface of the forming surface, and the chip portion 20 is stuck on the chip holding base 50 (FIG. 9A
)). As the resin, for example, a mixture of an epoxy resin and an amine adhesive is used.

Finally, the chip holder 50 to which the chip part 20 is attached is attached to the base 10 using, for example, screws.
Secure to. As described above, the dresser 1 of the second embodiment is completed. The fixing method is not particularly limited.

According to the dresser 1 according to the present embodiment, it has the same effect as that of the first embodiment, and by having the chip holding base between the chip part and the base metal, only the chip part acts on the polishing pad. It becomes easy to let you. Specifically, when the polishing pad is soft and the protrusion of the chip part from the base metal is small, the polishing pad comes into contact with the base metal, and the pressure from the chip part against the polishing pad can escape to the base metal. There is sex. In order to avoid the above, there is a method of increasing the thickness of the chip portion using a thick Si wafer. However, in this embodiment, since a metal chip holder is used, the cost can be reduced.

As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and without departing from the spirit of the invention,
Various omissions, replacements, and changes can be made. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 Dresser 2 Dressing mechanism 3 Polishing head 4 Nozzle 5 Polishing pad 6 Turntable 10 Base metal 20 Chip part 21 Substrate 22 Protrusion 23 Diamond thin film layer 30 Base film 40 Resist film 50 Chip holder 100 Polishing apparatus

Claims (13)

With the base metal,
A chip portion that is provided on the base metal and includes a Si substrate having a protrusion on the top and a plane orientation of (111) plane; and a diamond thin film layer provided on the protrusion of the Si substrate;
Having a dresser. With the base metal,
A chip portion including a plurality of Si substrates provided on the base metal and having protrusions on the upper portion; and a diamond thin film layer provided on the protrusions of the Si substrate;
Having a dresser. The dresser according to claim 2, wherein the Si substrate has a (111) plane. The dresser according to any one of claims 1 to 3, wherein the base metal partially protrudes from a joint portion with the chip portion. The dresser according to claim 1, wherein the shape of the protrusion is a conical shape. Prepare a chip part in which a Si substrate having a plurality of protrusions on the surface is separated,
Forming a diamond thin film layer on the protrusion of the tip portion;
A method for manufacturing a dresser, wherein the tip portion having the diamond thin film layer formed on a base metal is provided. A plurality of the chip parts divided into pieces are prepared, and after forming a diamond thin film layer on the protrusions of the plurality of chip parts, the plurality of chip parts are provided on the base metal. Item 7. A method for producing a dresser according to Item 6. The method of manufacturing a dresser according to claim 6 or 7, wherein the Si substrate has a (111) plane orientation. The method of manufacturing a dresser according to claim 6, wherein the Si substrate is a Si wafer. The method for manufacturing a dresser according to claim 6, wherein the shape of the protrusion is a conical shape. 11. The dresser manufacturing method according to claim 6, wherein the chip portion is provided on a chip holding base partially formed on the base metal. 11. The method for manufacturing a dresser according to any one of claims 6 to 11, wherein the plurality of protrusions on the surface of the Si substrate are simultaneously formed by etching. Using a dresser in which a diamond thin film layer is provided on the protrusions of each chip part obtained by dividing a Si substrate having a plurality of protrusions on the surface, and each chip part is provided on a base metal A method for manufacturing a semiconductor device, wherein a pad is sharpened and a semiconductor wafer is polished using the sharpened polishing pad.

Images